1895. NOTES AND COMMENTS. 30? 



among existing monkeys. The existing primates, including man, 

 have diverged in different directions from common ancestors, and the 

 presence of scattered resemblances among existing forms is precisely 

 what theory demands. 



The Alkaline Secretions of Moths. 



Recently, Mr. Oswald H. Latter showed that a nmnber of 

 moths assist their emergence from the cocoon by softening its anterior 

 end with a strongly alkahne fluid. In a recent communication to the 

 Entomological Society of London, he described a method by which 

 he was able to collect from the mouths of moths on the point of 

 emerging from the cocoons considerable quantities of the fluid. 

 Analysis showed that it contained 1-4 grammes of potassium 

 hydroxide in every 100 c.c. The fluid is contained (in the case of 

 Dicranura viunla) in a diverticulum of the mesenteron, which grows out 

 during pupal life immediately behind the stomodaeum. The digestive 

 fluids of the larvae are strongly alkaline. When the caterpillar 

 becomes a chrysalis, the digestive fluids have no longer any work to 

 do; they are stored up, and perhaps concentrated in the diverticulum, 

 and are thus ready to be discharged when the moth is on the point of 

 emergence. 



In the same paper, Mr. Latter mentions his discovery of another 

 interesting structure, which he has not yet been able to investigate in 

 detail. At the time of emergence, a shorr, wide tube opens into the 

 posterior third of the rectum at one end ; at the other it opens into 

 the body-cavity. This tube is full of a reddish fluid which is dis- 

 charged copiously from the rectum immediately after the emergence 

 of the imago. We trust that Mr. Latter will speedily give us further 

 information as to the origin and fate of this remarkable structure. 

 Any openings into the coelome are of morphological interest. 



Veiled Medus.e. 



In most of the text-books of zoology, as W. K. Brooks points 

 out in his paper on "The Sensory Clubs or Cordyli of Laodice" 

 {Journal of Morphology, 1895), it is laid down that there is a funda- 

 mental distinction between the sense-organs of the veiled Medusae 

 that come from hydroid stocks and those of the veiled Medusae which 

 develop directly from the egg. The Hertwigs first made the 

 distinction, and it was adopted by Haeckel. It was supposed that 

 Medusae with direct development (Trachymedusae) had auditory 

 clubs with sense-cells of ectodermal origin, while the concretions 

 within these (otoliths) were endodermal. Veiled Medusae that 

 develop from hydroids were supposed to have marginal sense-organs 

 composed of vesiculated, concretionary, ectodermal cells and sensory 

 cells with sensory hairs supplied from the lesser nerve-ring. 



Mr. Brooks has now shown that in many of the " Leptolinae," in 



